State-of-the-Art Ceramic Membranes for Oily Wastewater Treatment: Modification and Application

Abstract

Membrane filtration is considered to be one of the most promising methods for oily wastewater treatment. Because of their hydrophilic surface, ceramic membranes show less fouling compared with their polymeric counterparts. Membrane fouling, however, is an inevitable phenomenon in the filtration process, leading to higher energy consumption and a shorter lifetime of the membrane. It is therefore important to improve the fouling resistance of the ceramic membranes in oily wastewater treatment. In this review, we first focus on the various methods used for ceramic membrane modification, aiming for application in oily wastewater. Then, the performance of the modified ceramic membranes is discussed and compared. We found that, besides the traditional sol-gel and dip-coating methods, atomic layer deposition is promising for ceramic membrane modification in terms of the control of layer thickness, and pore size tuning. Enhanced surface hydrophilicity and surface charge are two of the most used strategies to improve the performance of ceramic membranes for oily wastewater treatment. Nano-sized metal oxides such as TiO2, ZrO2 and Fe2O3 and graphene oxide are considered to be the potential candidates for ceramic membrane modification for flux enhancement and fouling alleviation. The passive antifouling ceramic membranes, e.g., photocatalytic and electrified ceramic membranes, have shown some potential in fouling control, oil rejection and flux enhancement, but have their limitations.

Melded ceramic membranes: A novel fabrication method for ultrathin alumina membranes of high performance

“…The increased internal fouling was also evident in the FRR measured after each cleaning cycle (Figure 10C). When internal fouling is increased, the foulants will block a portion of the pores, leading to a reduced pure water flux 27 . The reduction in pure water flux is a result of the irreversible fouling.…”

“…When internal fouling is increased, the foulants will block a portion of the pores, leading to a reduced pure water flux. 27 The reduction in pure water flux is a result of the irreversible fouling. As shown in Figure 10C, after three chemical cleaning cycles, M12 had the least irreversible fouling at 8.60%, while C1 and C2 had the worst irreversible fouling, at 10.22%, and 22.20%, respectively.…”

An Overview of Membrane Distillation Technology: One of the Perfect Fighters for Desalination

“…Several techniques can be used to separate the oil from water such as skimming, coagulation, de-emulsification, frothfloatation, gravity, aerobic, and fermentation. [38][39][40] These all are traditional methods. The membrane-containing techniques are leading because of many factors for example high efficiency and purity.…”

“…11 Interaction between the oil droplets and membrane. Reproduced with the permission from [40], Copyright 2018 MDPI.…”

Membrane Separation Used as Treatment of Alkaline Wastewater from a Maritime Scrubber Unit

“…The choice of membrane material is determined by their properties regarding the treated suspension. In the field of membrane filtration, ceramic membranes are well established to treat wastewater containing a high proportion of organic matters mainly due to their properties [ 39 , 40 ]. Furthermore, compared to conventional mineral ceramic membrane materials, silicon carbide (SiC) membranes present the highest permeability (>3000 L h −1 m −2 ) [ 41 ] due to their very low tortuosity, their good chemical resistance, and their mechanical strength [ 42 ].…”